package com.myhome.demo;

import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.UUID;

public class StringDemo {

    public static void main(String[] args) {
        //test01();
        //test02();
        test03();
    }

    public static void test01() {
        String a = "abcd";
        String b = "abc" + "d";
        System.out.println("......" + (a == b));

        String c = new String("wer23");
        String d = new String("wer23");
        System.out.println(">>>>>" + (c == d));
    }

    private static Integer[] arr = {1, 2, 3, 4};

    private static void test02() {
        System.out.println(UUID.randomUUID().toString().replace("-", ""));
        System.out.println(Arrays.asList(arr).contains(2));
    }


    public static void test03() {
        Map<String, String> map = new HashMap<>();
        String iii = map.get(null);
        System.out.println("....." + iii);
    }

}
